Which of the following is NOT a component of a farm tap regulatory system?

The correct choice indicates that a gas meter adjustment is not considered a component of a farm tap regulatory system. A farm tap is designed to safely manage the flow of gas from a transmission line to a distribution system at a farm. The key components in such a system typically include items that control pressure and direction of gas flow.

The pin-off tee is included as it is a fitting that allows for a connection in the pipe system, ensuring gas can be directed to various outlets as needed. A mechanical union often serves as an assembly point for pipes, providing a means to connect and disconnect sections of the system easily. The regulator with a directional flow arrow is critical because it indicates the correct flow direction of gas, ensuring safe and proper operation.

By understanding that the gas meter adjustment relates more to measuring and not directly to the regulation or management of pressure and flow in a farm tap context, it becomes clear why it does not fit as a fundamental component of such a regulatory system.